The transformer vector group is indicated on the name plate of transformer by the manufacturer. The connection of all the windings in a threephase transformer is indicated by a vector group symbol. Different converters require different transformer con. For example, a transformer with a vector group of dy1 has a deltaconnected hv winding and a wyeconnected lv winding. Application of transformer according to vector group. This symbol indicates the winding connections and their relative phase displacement by means of a numerical index e. The vector group indicates the phase difference between the primary and secondary sides, introduced due to that particular configuration of transformer windings connection.
The vector diagrams are given in the name plate details of the transformer. Hence every electrical power transformer must undergo through vector group test of transformer at factory site for ensuring the customer specified vector group of. It means lv winding,which is star connected written in small letters means lv side and vice versais 30 degrees lagging by hv winding which is delta connected. Both the following ratiometer connections are correct for vector connection dyn11.
Basic idea about transformer vector group in theory of a threephase transformer works like three equal and separated singlephase transformers working separately with three phase system with shared limbs. Aug 07, 2019 dyn11 transformer vector group pdf read 6 answers by scientists with 1 recommendation from their colleagues to the question asked by parth panchal on feb 11, the vector group designation. Vector group test of power transformer electrical4u. When pair of coil of transformer have same direction than voltage induced in both. Hence every electrical power transformer must undergo through vector group test of transformer at factory site for ensuring the customer specified vector group of transformer. Contents hide 1 basic idea about transformer vector group 1.
Transformer vecttransformer vector group test conditionsor group. Transformer testing dyn11 transformer power electronics free. But after the winding connection is made it is necessary to check if the desired vector group has been achieved. Winding resistance measurement iec 600761 turns ratio measurement iec 600761 oltc analysis iec 602141 transformer demagnetization. Threephase transformer connections and vector groups for. Here yy 0 will mean its both the windings are starconnected and phase displacement between primary and secondary emfs is zero degree. What is the test procedure of vector group of a transformer having. The real time examples for phasor groups of transformer are given here. Vector group of 3phase transformer electrical concepts. The transformer is the link between the supplying electrical grid and the converter. The vector group provides a simple way of indicating how the internal connections of a transformer are arranged.
The first letter d refers to the primary configuration being a delta connection the y refers to the secondary configuration being a star connection. The three phase transformer is connected in various ways. This was done in order to create a notation for threephase transformer winding configuration. Vector group of transformers transformer electric power. The determination of vector group of transformers is very important before connecting two or more transformers in parallel. What is meant by vector group for transformers and why is it. It is a major component in the transformerconvertermotor chain. Transformer vector group test conditions ynd1, ynd11, dyn11, ynyn0. Dy1 would hence be a delta primary, wye secondary and a vector diagram with the reference vector pointing at 1 oclock.
The phase angle of the lv winding lags the hv by 30 degrees. Oct 14, 2018 the real time examples for phasor groups of transformer are given here. Basically this vector group arrangement will define the physical displacement of the generator shaft and the electrical phase of. Because there are 12 hours on a clock, and a circle. Mainly, the type of transformer connections are divided in 4 below groups. Why vector group of distribution transformer is dyn11. We do this testing to check that vector group of transformers in. The numerical index of the vector group comes from the clock hour gure the phase voltage hand 2u is at when the phase voltage hand of the high voltage winding 1u is at 12 oclock.
Transformer testing dyn11 free download as pdf file. May 11, 2011 dy1 would hence be a delta primary, wye secondary and a vector diagram with the reference vector pointing at 1 oclock. From your question above, i presume that ur understanding of the transformer is not complete. Dyn11 transformer vector group pdf read 6 answers by scientists with 1 recommendation from their colleagues to the question asked by parth panchal on feb 11, the vector group designation. The transformer vector group show the phase difference between the primary and secondary sides of the transformer. Through vector group of a transformer we can know that the winding configuration of a transformer. Dv power smart test instruments for reliable electrical. Transformer vecttransformer vector group test conditionsor group test conditions. A vector group is the international electrotechnical commission iec method of categorizing the high voltage hv windings and low voltage lv winding configurations of threephase transformers.
Transformer nameplates carry a vector group reference such at yy0, yd1, dyn11 etc. Vector group test of transformerthe vector group of transformer is an essential property for successful parallel operation of transformers. By far the most common vector configuration of three phase transformers we manufacture is the dyn11 vector group. Note that the highvoltage hv side always comes before the lowvoltage lv side, regardless of which is the primary winding. Significance of vector group of transformer your electrical. The transformer can either be dyn5 or dyn11 or of any other vector group. The auxiliary transformer is a dyn11 or any other vector group transformer and can be supplied in copper or aluminium with or without an off circuit tap changer. The clock method is used to produce the numerical index of the vector group, with each hour representing 30. Significance of vector group of transformer on the nameplate of threephase transformer vector group is printed as yy 0, dd 1 etc. Performing transformer vector group test prepared by ir kamarul.
In many cases a multitude of secondary windings, connected with different phase angles is required and special technical. I believe most 3 phase textbooks have the vector diagram with the reference vector at 0 degrees on the xaxis, which would equate to. Three phase transformer vector grouping significance. Normally dyn11 vector group using at distribution system. Pdf transformer vector group test conditions k pandian. This relatively simple nomenclature provides important information understanding vector group of transformer part 1 the primary windings are connected in one of. Transformer vector group connections are made based on the winding polarity. The following will tell you the suggestions with reasons. For parallel operations, one of the internal connections of all the three winding of one of the transformers on one side only either hv or lv is necessary to be changed. Dec 12, 20 application of transformer according to vector group. Standard types supplied with separate primary and secondary windings.
Dec 22, 2017 description of vector group testing of vector group bangla tutorial for power point slide go to eee practical knowledge. Dd0, dyn5, dyn11, yyn0, yd1, yd11, dz0, yz1 and yz11. Aim of vector group test is at site is to check if their is any damage in the windings during transportation and erection. What is the test procedure of vector group of a transformer. The vector group indicates the phase difference between the primary and secondary sides, introduced due to that particular configuration. I have faceting problem in testing of transformer vector group. Transformer vector group dyn11 and dyn1 physics forums. Dyn11 is vector group representation of 3 phase transformers in electrical engineering, a vector group is the international electrotechnical commission iec method of categorizing the high voltage hv windings and low voltage lv winding confi. Description of vector group testing of vector group bangla tutorial for power point slide go to eee practical knowledge. Every transformer contains its own vector group as shown below figure. Because generating transformer are ynd1 for neutralizing the load angle between 11 and 1. According to iec764, the value of vector group can be 0,1,2,4,5,6,7,8,10,11. Vector group of 3 winding transformer cr4 discussion thread.
The standard test usually links the a and a terminals then applies a suitable safe test voltage to the hv winding, and the resulting voltages between terminals prove the vector group. The naming convention popularly known as vector group of transformer was established by the international electrotechnical commission iec through iec 600761. Based on a previous discussion with a manufacturer, he said that the structure dyn11 is also simple in comparison with some other vector groups. The vector group also determines the phase displacement between the primary and the secondary winding, each unit in the vector group refers to 30 degrees displacement. Why are ynd1ynd11 the most common vector groups for power. P department of electrical and electronics engineering loyola institute of technology and science loyola nagar, thovalai, tamilnadu629302, india abstract transformer is the most important unit in an electrical distribution network. Note that the highvoltage hv side always comes before the lowvoltage lv. Vector group is punched on the name plate based on the user requirement by the manufacture. Please note that u cannot have two different vector group on a single transformer,i.
Rphase hv and rphase lv shorted for all vector group of transformer. I believe most 3 phase textbooks have the vector diagram with the reference vector at 0 degrees on the xaxis, which would equate to 3 oclock, then with b at 11 oclock and c at 7 oclock. It also determines the high voltage and low voltage windings arrangement of three phase transformers. Heat run test iec 600762 excitation current measurement. So a vector group dyn11 is delta on primary, star on secondary, with. The vector group designation indicates the windings configurations and the difference in phase angle between them. The phase sequence or the order in which the phases reach their maximum. May 23, 2012 application of transformer according to vector group. The vector group of transformer is an essential property for successful parallel operation of transformers.
Vector group test of power transformer electrical study app. Here yy 0 will mean its both the windings are starconnected and phase displacement between primary and secondary emfs is zero. These phasor groups can be better understand by the following examples. The systems phase sequence should be 1u, iv, 1w, or r, s and t the following are the most common threephase connections. Hi, all the transformers in a subtransmission network are dyn11, in another part of the network a transformer with the vector group of ynd1 is going to be used for an industrial complex.
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